1. Field of the Invention
Embodiments of the present invention relate to pylons that couple an externally attached component to an aircraft wing or fuselage. More particularly, embodiments of the present invention relate to aircraft engine pylons constructed from truss-shaped components that are joined together.
2. Description of the Related Art
An aircraft pylon secures an aircraft engine, typically a high-bypass engine, to an aircraft wing. The pylon performs a number of critical functions such as supporting the engine weight, the fairings and systems, providing a fire and vapor barrier between the engine and the wing, transmitting the engine thrust into the structure of the airplane, supporting engine nacelle and thrust reverser in the optimum aerodynamic location, and the like. A typical pylon may include nearly a hundred parts, which may be held together by thousands of fasteners. The assembly of the pylon may include drilling hundreds of holes for coupling the parts together as well as extensive corrosion protection and sealing of joints and fasteners. The strength of the materials required for the pylon may make the drilling process very time consuming. Furthermore, the use of mechanical fasteners requires considerable overlapping of the joining surfaces which adds weight and cost. Thus, the production of aircraft engine pylons from a large number of joined-together components is time and labor intensive with a high part count and corresponding high cost.
One approach to alleviate some of these problems involves casting the aircraft pylons as a single integrated molded structure. However, castings of this nature have a high cost and present logistical issues. For example, casting of a flowable metal into a mold that forms the pylon is limited by the maximum pour weight of the metal foundry, which in turn may limit the size of the pylon that can be produced or may force a number of castings of portions of the pylon to be produced that need to be joined together. The use of fasteners to join the portions together leads to the problems discussed above.